Process of treating iron or steel objects.



No. 827,802 f n PATBNTBD AUG. 7, 190:.l H. L. HoLLIs. PROCESS 0FTREATING IRON 0R STEEL OBJECTS.

APPLICATION FILED- JULY 7 1905.

unir-nn STATES PATENT OFFICE.

f HENRY L. HOLLIS, or CHICAGO, ILLINoisf PnOOE'ss OF TREATING IRON onSTEEL OBJECTS.

Specification of Letters Patent.

Patented Aug. 7, 1906. Y

applicati@ andv my '1. 1905. serial no. '268.8'01.

To all whom it may concern? Be it known that I, HENRY L. HOLLIS, acitizen of the United States, residing at Chicago;in the county of Cookand State .of Illinois, have invented a certain new and useful.Improvement in the Process for Treating Iron or Steel Objects, of whichthe following is a full, clear, concise, and exact description,reference being had to the accompanying drawings, forming a part of thisspecification.

My invention relates toA an improved method for treating ironor steelobjects, which may be in the form of sheets, in order to provide themwith a preservative coating.

In Patent No. 621,084, granted me March 14, 1899, I describe a methodfor applying a preservative coating to iron or steel objects,

which consists in temporarily inserting the object to be treated in asolution of caustic alkali as an electrolyte, temporarily connectingsaid obj ect as an anode, with a source of electricity, passing electriccurrent from said source through the object and electrolyte, wherebyoxidizing conditions will be furnished at the surface of the object andoxygen'will there be united with the iron to form a protective coating,and then withdrawing the connected iron object from the solution.

In Patent N o. 664,550, granted me December 25, 1900, a similar'methodof treatment is described. In this method the object is rst made acathode for the purpose of cleansing it from foreign material,whereafter the object is made an anode and the process carried out asdescribed in the other patent mentioned. During the coating, however, ofthe object foreign substances are mechanically deposited thereon whichinterfere with the uniform appearance of the object or sheets, and if itis attempted to brush or rub these sheets off dry the surface thereofis.. -likely to become marred. I find that by treating the obj ects withoil subsequent to the coating thereof they may readily be brushedandcleaned Without marring or scratching them, and the oil treatment,furthermore, gives a much more uniform appearance and allows the objectsto be packed and handled with muchless danger of scratching. The objectsalso even after the oil is apparently completely and thoroughly rubbedoff are found less 'liable to rust than without this oil treatment.

The entire for treating the object is as follows:

pgocess shown in Fig. 1, the object a to be treated is immersed in thesolution b, which forms the electrolyte and is adapted through theswitch c to be connected with either terminal of the sourcev of currentd, the

plate e also in the electrolyte being connected with the current sourceto complete the circuit. If the object, such as the sheet shown, issufliciently clean, it-may at once be connected with the source to formthe anode, and current then ilowing from the object to the electrolytecauses oxidizing conditions to set to adhere to the object, and it isvery diflicult to brush these olf without marring or scratch- 'ing theobjects. After the coatingis applied I therefore dry the objects andthen immerse them for a very short time in a bath of oil,

which is preferably heated, the degree of heat depending on the kind ofoil. With a mineral oil the temperature is kept below theflashing-point; but I ind that very good results can be obtained byusing palm-oil, the temperature thereof beingraised to approximately 125centigrade. After removing the objects from the oil-bathV they arebrushed or rubbed with bran or any other material that willnot scratchthe sheets, but will absorb and remove the oil. This treatment mightalso be carried 'on with oil at ordinary temperatures; but the use ofheated oil is much more economical for the reason that the oil in aheated condition runs OH" the objects much more rapidly and completely,also lessens the labor in ment.

Objects treated in this manner require much less care in handling andpacking, as

the danger to marring or scratching is greatly lessened on account of.the oil treatment, and

the objects will also resist rust for a much longer time.

The electrolytic'solution may be any suitable oxidizingand cleaningreagent, such as caustic soda or any other caustic alkali.

and thereby the cleaning treatthe electrolyte and object wherebyoxidation will take place at the surface of the object and oxygen willthere be united with the iron to form a the object rom the solution anddrying it,

and then immersing the object in oil.

2. The method of providing'a protective coating for iron objects whichconsists in immersing the object in a suitable electrolyte, passingcurrent throughI the electrolyte and object to cause oxidizingconditions at the surface of the object, whereby oxygen will be unitedwith the iron to form a coating, removing the obj ect from theelectrolyte and drying it, immersing the object for a short time in oil,and then rubbing off the oil with soft material. l

3. The method of providing a preservative coating to iron objects whichconsists in subjecting the iron object to oxidizing conditions to formthereon a coating, thereafter immersing the object in oil, and thenrubbing off the oil. C

4. The method of treating an iron obj ect to provide a protectivecoating therefor which consists in causing oxidation of the iron toiformthereon a protective coating of -iron oxid, thereafter immersing theobject in oil, and then removing the oil therefrom.

5. The method of treating iron objects to provide a preservative coatingtherefor which consists in subjecting the iron to oxidizing infiuence toform thereon a coating of iron oxid, thereafter temporarily immersingthe object in heated oil and then absorbing and rubbing off the oil.

6. The method of treating iron objects to rotective coating,withdrawingl provide therefor a preservative coating which consists inelectrolytically causing the formation of a coating of iron oxidthereon, drying the obj ect, and immersing it in oil.

7. The method of treating iron objects to provide therefor apreservative coating which consists in electrolytically causing theformation of a coating of iron oxid thereon, drying the object,immersing it in oil, and then absorbing and rubbing od the oil.

8. The method of treating iron objects to provide a preservative coatingtherefor which consists in electrol tically causing the formation of acoatingo iron oxid thereon, drying the object, immersing it temporarilyin heated oil, and then absorbing and rubbing off superfluous oil.

9. The method of treating iron objects to provide a protectivecoatingtherefor which' consists in immersing the object in anelectrolyte, causing -the passage of current through the electrolyte andobject to cause the formation of a coating thereon, removing the obj ectfrom the electrol teand drying it, thereafter immersing the o ject temorarily in a bath of heated oil, and then rub ing the object with softmaterial to dry it from the oil. f

10. The method of treating iron objects to provide a protective coatingtherefor Which consists in immersing the object in an electrolyteconsisting of caustic alkali, suitably passing a current of electricitythrough the electrolyte and obj ect to cause formation of a coating onthe object, removingthe object from the electrolyte and drying it,thereafter immersing the object for a short time in a bath of heatedoil, and then rubbing the object with bra`n, sawdust or other softmaterial to absorb and dry the oil therefrom.

In witness whereof Ihereunto subscribe my name this 1st day of July, A.D. 1905.

HENRY L. HQLLIS.

Witnesses:

Arron HUNTER, CHARLES J. SCHMIDT.

